Asthma is a common and complex disorder. In the U.S., the burden of asthma is enormous, with a disproportionate impact on vulnerable groups including young children, African-Americans and those living in the inner city. These most vulnerable people often inhabit an environment that has excessive pollution levels, including high levels of indoor pollutants and allergens. Furthermore, the diet of low-income, inner city African-Americans is markedly inconsistent with national nutritional guidelines, and has a pattern that may leave them especially vulnerable to the effects of inhaled pollutants and allergens. To address the critical questions of the role of dietary intake and the indoor environment on childhood asthma, we propose a panel study of children living in urban neighborhoods enriched with African-American and lower income participants. We have already shown that in the neighborhoods of the proposed study participants that in-home pollutant levels, including particulate matter (PM) and nitrogen dioxide (NO2), greatly exceed the outdoor levels and suburban indoor levels and that these in-home pollutants are independently associated with increased asthma morbidity. Furthermore, we have already demonstrated that the diet in this high-risk population is poor and is of a pattern that is inconsistent with dietary patterns that have been shown to protect against asthma. We plan to examine the effect of the poor inner city diet on susceptibility of asthmatic children to in-home pollutant (PM and NO2) exposure (Aim 1), and to identify barriers and enabling factors to implementing dietary and environmental modifications in inner city homes of children with asthma (Aim 2). To address these aims will plan to recruit 200 children with asthma, ages 5-12, in inner city Baltimore, each of whom will undergo 3 seven-day monitoring periods (at baseline, 3 months and 6 months) where they will undergo indoor air monitoring, dietary and respiratory assessments, nasal lavage, exhaled nitric oxide measurements, urine collection and blood draw for markers of inflammation and oxidative stress. Importantly, the aims in this application build upon the well-established infrastructure of a group of experienced investigators with diverse but highly integrated areas of expertise. This real-world field-based study will complement the findings from Projects 2 and 3 by demonstrating the clinical effect of diet on response to indoor pollutants, and by providing corroborative evidence of the oxidative stress and inflammatory pathways by which they may act. Projects 2 and 3 will similarly examine the effects of diet on response to pollutants, but in controlled settings using human subjects and animal.